Whose code is it
South Carolina's Building Codes Council adopts the International Code Council family — including the mechanical and plumbing codes — on a statewide cycle, with the currently adopted editions published by the Council.
Local jurisdictions enforce those adopted codes through their building departments; that enforcement, not the paperback on a shelf, is what your inspection tests against.
What inspections verify on HVAC
After an installation, inspectors broadly confirm the equipment is installed per manufacturer listing and code: clearances and access, electrical disconnects, condensate drainage with overflow protection where required, refrigerant line practice, and combustion venting on gas equipment.
None of it is bureaucratic decoration — every item traces to a house fire, a ceiling collapse, or a carbon monoxide case somewhere in the code's history.
The water heater checklist
Water heater replacements carry their own code items where the adopted plumbing code applies: temperature-and-pressure relief discharge piped safely, drain pans with drains where leaks would damage the home, thermal expansion control where the supply is a closed system, and proper venting or electrical connection by fuel type.
It is why a code-compliant replacement quote can differ from a swap-it-cheap quote — the missing items are the difference.
Ducts, energy, and verifying your contractor
Duct sealing and insulation requirements in unconditioned spaces come along with the adopted energy code — another reason crawl-space duct replacements are quoted the way they are.
Before any significant work, verify your contractor's license on the state's public lookup and ask who pulls the permit. Licensed contractors expect both questions.
